ABSTRACT
Background: Among the allelic variants of blood groups, the molecular characterization of ABO blood group has clinical and anthropological importance. Aim: To perform a characterization of the molecular variants of the allele ABO*O of the ABO blood group. Material and methods: Eighty four subjects of Aymara origin, living in Northern Chile, 75 individuals of Huilliche origin, living in Southern Chile and 82 subjects living in Santiago (Central Chile), were studied. All individuals were of group O, homozygotes for G261- deletion, that defines O1 alleles. Mutations G188A, G261-, G542A, T646A and C771T, described for alleles O1, O1variant and G542A were determined by PCR-RFLP (polymerase chain reaction-restriction fragment lenght polymorphism). Results: Allele O1variant has frequencies of 0.65, 0.81 and 0.6 in Aymara, Huilliche and Santiago subjects, respectively. The figures for allele O1 are 0.35, 0.19 and 0.4, respectively and those for the allele with G542A mutation are 0.119, 0.113 and 0.079, respectively. Conclusions: These results are concordant with the reported higher frequency of allele O1variant in South American aboriginal populations. The frequencies of G542A allele in these Chilean individuals are lower than those described for Amazon aborigines.
Subject(s)
Humans , Genetic Variation , ABO Blood-Group System/genetics , Gene Frequency/genetics , Indians, South American/genetics , Mutation/genetics , Alleles , Chile , Exons/genetics , Genotype , Polymorphism, Restriction Fragment Length , Sequence Analysis, DNAABSTRACT
Background: There are geographic and ethno historic evidences that relate Paposo cove, located 150 km south of the city of Antofagasta, with old fishermen-collector populations known as Changos, that lived in that zone in the XVII and XVIII centuries. Aim: To perform a genetic and molecular characterization of current Paposo inhabitants, through mitochondrial DNA polymorphism analysis and molecular analysis of classical ABO and Duffy blood groups. Material and methods: Forty unrelated individuals were studied. The presence of restriction polymorphisms that define A, B, C, and D Amerindian founder mitochondrial haplogroups was studied and molecular determination of classical blood groups were done by PCR. Results: One individual had A haplogroup (2.5 percent), 19 had B haplogroup (47.5 percent), six had C haplogroup (15 percent) and 11 had D haplogroup (27.5 percent). Three subjects (7.5 percent) did not have any of these haplogroups. Among ABO blood groups, the frequency of O101 allele was 0.39, that of allele O201 was 0.53 and that of A allele was 0.08. Duffy blood group frequencies were 0.58 for FY*A and 0.42 for FY*B. FY null allele was not found. Conclusions: The frequency distribution of Amerindian mitochondrial haplogroups in Paposo inhabitants suggest that these individuals are related with Aymara and Atacameño Amerindians that can be considered culturally and geographically close populations. This proposal is supported by the results of the molecular determination of classical blood groups. Our findings in Paposo cove may represent the distribution of these markers in Chango Indians, of whom there is limited physical evidence and that became extinct near 1890 (Rev Méd Chile 2004; 132: 663-72).
Subject(s)
Humans , Gene Frequency/genetics , Haplotypes , Genetic Markers/genetics , Chile/ethnology , Indians, South American/geneticsABSTRACT
Genes for dopamine receptor DRD4 and dopamine transporter DAT1 are highly polymorphic. Two alleles of these genes, namely the DRD4.7 and the DAT1*9 are frequently associated to the attention deficit disorder with hyperactivity. In Europe, the allele for DRD4 receptor with four repetitions (DRD4.4) has the highest frequency, with a median of 69 percent, followed by DRD4.7, with a frequency of 15 percent. South American indigenous populations have higher frequencies for DRD4.7 (61 percent) than for DRD4.4 (29 percent). The ten repetition allele for DAT1 transporter has a high frequency among Europeans (72 percent) and Amerindians (100 percent). The allele DAT1*9 is the second most frequent allele. Aim: To study the frequency of DRD4 and DAT1 alleles in a Chilean population sample. Material and methods: One hundred serum samples were obtained from blood donors in two public hospitals in Santiago. Polymorphic regions for DRD4 and DAT1 were amplified by polymerase chain reaction. Results: The allele DRD4.4 had a frequency of 59 percent and DRD4.7 a frequency of 27 percent. The allele DAT1*10 had a frequency of 74 percent, followed by DAT 1*9, with a frequency of 23 percent. Discussion: In a Chilean population sample, the frequency of DRD4 and DAT1 alleles was very similar to that of European populations
Subject(s)
Humans , Male , Adolescent , Adult , Female , Substance-Related Disorders , Genetic Markers/genetics , Receptors, Dopamine/genetics , Alleles , Gene Frequency , Mental Disorders , Nervous System Diseases , Genetics, Population , Carrier Proteins/geneticsABSTRACT
Background: The analysis of mitochondrial DNA restriction site polymorphisms assigns most Latin American aborigines to four haplogroups. These are characterized by determined polymorphic restriction sites and a deletion of 9 base pairs in the intergenic region V. Aim: To study the distribution of mitochondrial DNA haplogroups in Chilean aboriginal groups, as well as in the mixed population of Santiago. Material and methods: One hundred twenty Aymara subjects and 23 Atacame-o subjects from the Northern part of Chile and 162 randomly chosen subjects residing in Santiago were studied. DNA was extracted from peripheral lymphocytes. Mitochondrial DNA was amplified by means of polymerase chain reaction. Results: The frequency of haplogroup B decreases from north to south. Aymaras in the north have the highest frequency (64 percent) and it is absent among the Yamanas (previously studied) in the extreme South. Haplogroups C and D show an inverse tendency. It is noteworthy that 84 percent of mitochondrial haplogroups of the mixed population of Santiago are of Amerindian origin whereas the Y-chromosomes are mainly European. Conclusions: The peculiar distribution of haplotypes indicate that the population of Santiago is the result of an asymmetric mating system in which the females ancestors were mainly Amerindian and the male ancestors mainly European
Subject(s)
Humans , DNA, Mitochondrial , Polymorphism, Genetic/genetics , Haplotypes , Indians, South American , Genetics, PopulationABSTRACT
Using and Elisa technique, IgG antibodies against hepatitis E virus were measured in 40 alcoholics, 40 hemophilics, 174 blood donors, 36 subjects with acute non A non B non C hepatitis and 66 subjects with acute hepatitis A. Antibodies were detected in 1 alcoholic (2,5 percent), 3 hemophilics (7,5 percent), 7 blood donors (4 percent), 3 patients with non-A-non-B-non-C hepatitis (8,3 percent) and 3 patients with acute hepatitis A (4,5 percent). A low frequency of hepatitis E infection was detected in the studied subjects